The exhaust-gas processing technique that uses a solid material such as a capture material or a catalyst to capture specific gas from exhaust gas, desorbs and separates the captured gas, and neutralize the separated gas has been applied to a lot of fields including power plants, synthetic plants, and automobiles, and systemized. However, in most cases, since the exhaust gas emitted from the plants and so on contains components that deteriorate the capture material or catalyst, the capture material or catalyst deteriorates with time. Therefore, to detect the deterioration level of the capture material or catalyst and efficiently manage the system is important in improving the operation and reducing running costs in exhaust-gas processing equipment.
For example, in the exhaust-gas treatment equipment that uses a carbon dioxide (hereinafter referred to as CO2) capture material to recover CO2 from a boiler exhaust gas of a thermal power plant, the boiler exhaust gas contains components that deteriorate the CO2 capture material, such as SOx, NOx, and smoke and dusts. Accordingly, if the CO2 capture receives such components incoming, the CO2 capture material deteriorates in CO2 capture performance with time. After capturing CO2, the CO2 capture material is caused to desorb the captured CO2 by heating or depressurization, and is continuously reused for capture of CO2. The CO2 capture performance of the CO2 capture material can be also lowered due to thermal and pressure hysteresis caused by repeated cycles of capture and desorption.
Generally, the CO2 capture material generates heat at capture of the CO2. Thus, when the CO2 capture performance lowers, the amount of captured CO2 decreases, in turn, the amount of generated heat decreases. Accordingly, by measuring the temperature of the CO2 capture material in the flow of the exhaust gas containing CO2, the deterioration state of the CO2 capture material can be indirectly recognized. For example, Patent literature 1 discloses the technique of estimating the deterioration state of a catalyst according to position in a reaction container by installing a plurality of temperature measuring elements along the flow of gas in the reaction container filled with the catalyst, and monitoring temperatures of the catalyst using the installed temperature measuring elements.